sound methods of weed control, but also enhance the use of microorganisms in other areas of agriculture and the environment for as many applications as we care to imagine and discover.
Microorganisms can significantly influence the distribution, abundance, and competition among plant species, and thus they can be used in biological weed control programs. Deleterious rhizobacteria (DRB) are soil bacteria that colonize the rhizosphere and suppress plant growth by the production of phytotoxic substances. These substances can impair seed germination and delay plant development in specific plant species and cultivars. These DRB have the potential to be used to regulate the growth of weeds. Biological control of weeds using DRB while reducing weed pressures can reduce costs, the need for tillage, and synthetic pesticide use. We have isolated soil bacteria that are selective in their suppression of various weed species and are effective in reducing weeds when they are applied to the field. These bacteria are excellent biological control agents because they are aggressive colonizers of the roots and residue, thereby functioning as a direct delivery system for the natural, plant- suppressive compounds they produce. A better understanding of the ecology of these bacteria and the weeds they suppress is needed for the successful use of this technology.
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